29-09-2016, 04:28 PM
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Introduction
It is dangerous to put limits on wireless.” - Guglielmo Marconi, 1932
There has been tremendous growth in wireless in the past 10 years. Even more in Europe and Asia than North America
Driven by technological advances – digital and RF circuit fabrication improvements, large scale circuit integration, miniaturization technologies, digital switching
Driven by business investment – although overinvestment has created bad profitability recently.
Driven by consumer demand – Regardless of current business profitability, the growth rate in terms of numbers of customers is substantial. The ability to communicate wirelessly is of obvious benefit to many. What are some of the benefits?
. History
Wired Communications
1834 - Gauss and Weber build telegraph system in Germany
1844 - Morse connects Baltimore and Washington by telegraph
1858 - First transatlantic telegraph cable laid
1876 - Alexander Bell demonstrates telephone
1911 - New York can telephone Denver
Wireless Communications --Not so “new”
Had slow growth at first compared to other inventions.
But now is growing very rapidly.
1899 - Marconi sends first radio message across Atlantic
1905 - Hulsmeyer detects ships with radar
1927 - US & Europe telephones linked by HF radio
1934 - AM mobile police radios for public safety widely used
1935 - Edwin Armstrong demonstrates FM radio system, became the primary modulation technique.
1940 - First microwave radar
1965 - First commercial communication satellite
1968 - AT&T proposes cellular phone system to Federal Communications Commission (FCC)
1983 - FCC allocates spectrum for analog cellular service (AMPS)
1990 - GSM digital cellular service introduced in Europe
1995 - FCC auctions new Personal Communication Service (PCS) licenses in U.S. for digital services
1998 - 40 million cellular phone users in U.S.
2000 - In some countries, mobile users outnumber conventional wireline customers.
2001 - 630 million subscribers worldwide (as compared to 1 billion wired phone lines.
2001 - Over 1% of worldwide wireless subscribers have abandoned wired telephone service for home use.
2005 − Over 130 million cellular phone users in U.S. (out of population of 300 million including children).